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Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

MAILING ADDRESS: 1120 SW 5th Ave, Room 1000, Portland, OR 97204

More Contact Info

1. Russian Knapweed

Russian knapweedRussian Knapweed (Acroptilon repens)

  • Blooms summer to fall
  • Cone-shaped flowering heads 1/4 to 1/2 inch wide with one flower, pink to lavender, growing at each branchlet tip
  • Grows up to 4 feet tall
  • Forms dense colonies with erect, branched stems

Photo by Eric Coombs, Oregon Department of Agriculture